It is a Jordan-Polya number, since it can be written as 8! ⋅ 2!.
It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.
It is an Ulam number.
It is an unprimeable number.
80640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
280640 is an apocalyptic number.
80640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 80640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159432).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
80640 is a wasteful number, since it uses less digits than its factorization.
80640 is an evil number, because the sum of its binary digits is even.
The square root of 80640 is about 283.9718295888. The cubic root of 80640 is about 43.2032919302.
The spelling of 80640 in words is "eighty thousand, six hundred forty".